Messages in this thread | | | From | Ingo Oeser <> | Subject | Re: undo an mke2fs !! | Date | Thu, 6 Nov 2003 15:25:41 +0100 |
| |
On Thursday 06 November 2003 14:34, Theodore Ts'o wrote: > On Wed, Nov 05, 2003 at 09:56:01PM -0800, Robert Gyazig wrote: > > Hi Ted and others, > > > > I created a new partition on my disk, and without > > noticing the change in the hdaX of the partition i did > > an mke2fs /dev/hdaX. :( > > > > Unfortunately it was my /home partition and was an > > ext3 partition earlier. Can anyone please advice on > > how to retrieve the old data. > > > > I read that mke2fs nukes all the meta information, so > > does that mean all inodes are destroyed and there is > > no hope for me ?!?!? > > Unfortunately, you're correct. The location of which blocks were > associated with which inodes are irretrievably lost. > > If you had backed up the metadata using an e2image command, you would > have been fine, but that command takes a while to run, so most people > don't bother to do this. (Not a bad idea for the absolute paranoids > in the house would be to run e2image out of a cron script and save the > image file on some *other* filesystem.) > > I've thought about making mke2fs run e2image and saving the result > somewhere else, but that takes a long time, and people would get > annoyed if I did that. Still, enough people have gotten screwed by > this that I've been tempted to add this as an option. Another > possibility is for mke2fs to notice when the filesystem is already > formatted using ext2/3, and then printing a warning message and > waiting 10 seconds before continueing, so the user has a chance to > type control-C. This would probably be the least annoying as far as > already existing scripts that use mke2fs, although of course there > would be an option to turn this behaviour off. > > > i did a cat /dev/hdaX > /dev/hdaY, which was an empty > > partition earlier so that I can play around a bit. I > > tried couple of things with debugfs but coudn't go > > much far. > > You can use a disk editor to find the text strings of critical files > that you wish to rescue, and hope they were contiguously allocated, > but that's probably the best you can do.... > > Sorry, but that's the current Unix design philosophy, which is to > assume that the system administrator knows what he/she is doing. I > never, ever type the mke2fs command without a certain amount of fear > and trepidition, and always check and triple check before doing so. > Still, as Linux becomes more mainstream, we do need to think about > adding safety checks so that to avoid accidents by less careful system > administrators. The challenge is to figure out ways of doing so in > the least obstrusive way as possible, to avoid annoying the existing > population. > > - Ted > > P.S. The other approach, which might also be the right one, is to use > a front-end program --- call it newfs --- which does many more safety > checks and which could do things like use e2image to backup the inode > blocks before doing an mke2fs. That way, administrators can choose > whether they want the additional safety checks or not. > > > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |